Saffron is the most expensive spice in the world. It is used in a variety of cuisines, as well as a fabric and skin dye. And just one pound of the spice can cost consumers $5,000 But just what makes saffron so wildly expensive? It's a complicated spice to harvest, requiring a lot of physical labor. Saffron comes from the saffron crocus flower, which has three red stigmas. The stigma is the female part of flower, which contains the saffron spice.